When vaccinated against Hib concomitantly with inactivated polio vaccine (IPV), much fewer antibodies to Hib are produced than if it were made simultaneously with a live polio vaccine. Also it was found that in children who simultaneously vaccinated against Hib and DTaP, much fewer antibodies are produced from tetanus.
Vaccines were pricked in different places (one in hand, the other in the leg). Previously, it was not known that if two vaccines were pricked simultaneously, interference. The anism of this phenomenon is unknown.
The combined DTaP/Hib vaccine produces significantly fewer antibodies from Hib and tetanus than if they were separately. More: , , . Hib in almost all countries is made up of a pentavalent or hexavalent vaccine, along with IPV and tetanus (pentaxime, pentasel, infarix, etc.)Non-pertussis components of combination vaccines: problems with potency testing. 1999, Sesardic, Biologicals
The combined DTaP/Hib vaccine (with acellular pertussis vaccine) produces 10 times less antibodies from Hib than the combined DTP/Hib vaccine. If you stab Hib and DTaP in the same place, 5-15 times less antibodies from Hib than if to prick them in different places.
DTaP produces significantly less antibodies from diphtheria than DTP.
After the UK switched to acellular pertussis vaccine (DTaP/Hib), almost a sevenfold increase in Hib cases was reported.